Netty 4.1.107.Final · io.netty.handler.codec.http.websocketx.extensions.WebSocketServerExtensionHandler

public Class WebSocketServerExtensionHandler

This handler negotiates and initializes the WebSocket Extensions. It negotiates the extensions based on the client desired order, ensures that the successfully negotiated extensions are consistent between them, and initializes the channel pipeline with the extension decoder and encoder. Find a basic implementation for compression extensions at io.netty.handler.codec.http.websocketx.extensions.compression.WebSocketServerCompressionHandler.

Modifier and Type	Field and Description
private final List<WebSocketServerExtensionHandshaker>	extensionHandshakers
private final Queue<List<WebSocketServerExtension>>	validExtensions

Modifier and Type

Field and Description

private final List<WebSocketServerExtensionHandshaker>

extensionHandshakers

private final Queue<List<WebSocketServerExtension>>

validExtensions

Constructor Summary

Access	Constructor and Description
public	WebSocketServerExtensionHandler(WebSocketServerExtensionHandshaker... The extension handshaker in priority order. A handshaker could be repeated many times with fallback configuration. extensionHandshakers) Constructor

Modifier and Type	Method and Description
public void	channelRead(ChannelHandlerContext ctx, Object msg) Overrides io.netty.channel.ChannelInboundHandlerAdapter.channelRead. Implements io.netty.channel.ChannelInboundHandler.channelRead. Calls `ChannelHandlerContext#fireChannelRead(Object)` to forward to the next `ChannelInboundHandler` in the `ChannelPipeline`.
private void	handlePotentialUpgrade(final ChannelHandlerContext ctx, ChannelPromise promise, HttpResponse httpResponse, final List<WebSocketServerExtension> validExtensionsList)
protected void	onHttpRequestChannelRead(ChannelHandlerContext ctx, HttpRequest request) This is a method exposed to perform fail-fast checks of user-defined http types.
protected void	onHttpResponseWrite(ChannelHandlerContext ctx, HttpResponse response, ChannelPromise promise) This is a method exposed to perform fail-fast checks of user-defined http types.
public void	write(final ChannelHandlerContext the `ChannelHandlerContext` for which the write operation is made ctx, Object the message to write msg, ChannelPromise the `ChannelPromise` to notify once the operation completes promise) Overrides io.netty.channel.ChannelDuplexHandler.write. Implements io.netty.channel.ChannelOutboundHandler.write. Calls `ChannelHandlerContext#write(Object, ChannelPromise)` to forward to the next `ChannelOutboundHandler` in the `ChannelPipeline`.

Modifier and Type

Method and Description

public void

channelRead(ChannelHandlerContext ctx, Object msg)

Overrides io.netty.channel.ChannelInboundHandlerAdapter.channelRead.

Implements io.netty.channel.ChannelInboundHandler.channelRead.

Calls ChannelHandlerContext#fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline.

private void

handlePotentialUpgrade(final ChannelHandlerContext ctx, ChannelPromise promise, HttpResponse httpResponse, final List<WebSocketServerExtension> validExtensionsList)

protected void

onHttpRequestChannelRead(ChannelHandlerContext ctx, HttpRequest request)

This is a method exposed to perform fail-fast checks of user-defined http types.

protected void

onHttpResponseWrite(ChannelHandlerContext ctx, HttpResponse response, ChannelPromise promise)

This is a method exposed to perform fail-fast checks of user-defined http types.

public void

write(final ChannelHandlerContext

the ChannelHandlerContext for which the write operation is made

ctx, Object

the message to write

msg, ChannelPromise

the ChannelPromise to notify once the operation completes

promise)

Overrides io.netty.channel.ChannelDuplexHandler.write.

Implements io.netty.channel.ChannelOutboundHandler.write.

Calls ChannelHandlerContext#write(Object, ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline.

extensionHandshakers	back to summary
private final List<WebSocketServerExtensionHandshaker> extensionHandshakers

extensionHandshakers

back to summary

private final List<WebSocketServerExtensionHandshaker> extensionHandshakers

validExtensions	back to summary
private final Queue<List<WebSocketServerExtension>> validExtensions

validExtensions

back to summary

private final Queue<List<WebSocketServerExtension>> validExtensions

Constructor Detail

WebSocketServerExtensionHandler	back to summary
public WebSocketServerExtensionHandler(WebSocketServerExtensionHandshaker... extensionHandshakers) Constructor Parameters extensionHandshakers:WebSocketServerExtensionHandshaker[] The extension handshaker in priority order. A handshaker could be repeated many times with fallback configuration.

WebSocketServerExtensionHandler

back to summary

public WebSocketServerExtensionHandler(WebSocketServerExtensionHandshaker... extensionHandshakers)

Constructor

Parameters

extensionHandshakers:WebSocketServerExtensionHandshaker[]: The extension handshaker in priority order. A handshaker could be repeated many times with fallback configuration.

Method Detail

channelRead back to summary

channelRead	back to summary
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception Overrides io.netty.channel.ChannelInboundHandlerAdapter.channelRead. Implements io.netty.channel.ChannelInboundHandler.channelRead. Doc from io.netty.channel.ChannelInboundHandlerAdapter.channelRead. Calls `ChannelHandlerContext#fireChannelRead(Object)` to forward to the next `ChannelInboundHandler` in the `ChannelPipeline`. Sub-classes may override this method to change behavior. Annotations @Override

public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception

Overrides io.netty.channel.ChannelInboundHandlerAdapter.channelRead.

Implements io.netty.channel.ChannelInboundHandler.channelRead.

Doc from io.netty.channel.ChannelInboundHandlerAdapter.channelRead.

Calls ChannelHandlerContext#fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Annotations

@Override

handlePotentialUpgrade	back to summary
private void handlePotentialUpgrade(final ChannelHandlerContext ctx, ChannelPromise promise, HttpResponse httpResponse, final List<WebSocketServerExtension> validExtensionsList)

onHttpRequestChannelRead back to summary

onHttpRequestChannelRead	back to summary
protected void onHttpRequestChannelRead(ChannelHandlerContext ctx, HttpRequest request) throws Exception This is a method exposed to perform fail-fast checks of user-defined http types. eg: If the user has defined a specific `HttpRequest` type i.e.`CustomHttpRequest` and `channelRead` can receive `LastHttpContent#EMPTY_LAST_CONTENT` `msg` types too, can override it like this: public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { if (msg != LastHttpContent.EMPTY_LAST_CONTENT) { if (msg instanceof CustomHttpRequest) { onHttpRequestChannelRead(ctx, (CustomHttpRequest) msg); } else { // if it's handling other HttpRequest types it MUST use onHttpRequestChannelRead again // or have to delegate it to super.channelRead (that can perform redundant checks). // If msg is not implementing HttpRequest, it can call ctx.fireChannelRead(msg) on it // ... super.channelRead(ctx, msg); } } else { // given that msg isn't a HttpRequest type we can just skip calling super.channelRead ctx.fireChannelRead(msg); } } Important Note It already call `super.channelRead(ctx, request)` before returning. Annotations @UnstableApi

protected void onHttpRequestChannelRead(ChannelHandlerContext ctx, HttpRequest request) throws Exception

This is a method exposed to perform fail-fast checks of user-defined http types.

eg:
If the user has defined a specific HttpRequest type i.e.CustomHttpRequest and channelRead can receive LastHttpContent#EMPTY_LAST_CONTENT msg types too, can override it like this:

    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        if (msg != LastHttpContent.EMPTY_LAST_CONTENT) {
            if (msg instanceof CustomHttpRequest) {
                onHttpRequestChannelRead(ctx, (CustomHttpRequest) msg);
            } else {
                // if it's handling other HttpRequest types it MUST use onHttpRequestChannelRead again
                // or have to delegate it to super.channelRead (that can perform redundant checks).
                // If msg is not implementing HttpRequest, it can call ctx.fireChannelRead(msg) on it
                // ...
                super.channelRead(ctx, msg);
            }
        } else {
            // given that msg isn't a HttpRequest type we can just skip calling super.channelRead
            ctx.fireChannelRead(msg);
        }
    }

Important Note

It already call super.channelRead(ctx, request) before returning.

Annotations

@UnstableApi

onHttpResponseWrite back to summary

onHttpResponseWrite	back to summary
protected void onHttpResponseWrite(ChannelHandlerContext ctx, HttpResponse response, ChannelPromise promise) throws Exception This is a method exposed to perform fail-fast checks of user-defined http types. eg: If the user has defined a specific `HttpResponse` type i.e.`CustomHttpResponse` and `write` can receive `ByteBuf` `msg` types too, it can be overridden like this: public void write(final ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception { if (msg != Unpooled.EMPTY_BUFFER && !(msg instanceof ByteBuf)) { if (msg instanceof CustomHttpResponse) { onHttpResponseWrite(ctx, (CustomHttpResponse) msg, promise); } else { // if it's handling other HttpResponse types it MUST use onHttpResponseWrite again // or have to delegate it to super.write (that can perform redundant checks). // If msg is not implementing HttpResponse, it can call ctx.write(msg, promise) on it // ... super.write(ctx, msg, promise); } } else { // given that msg isn't a HttpResponse type we can just skip calling super.write ctx.write(msg, promise); } } Important Note It already call `super.write(ctx, response, promise)` before returning. Annotations @UnstableApi

protected void onHttpResponseWrite(ChannelHandlerContext ctx, HttpResponse response, ChannelPromise promise) throws Exception

This is a method exposed to perform fail-fast checks of user-defined http types.

eg:
If the user has defined a specific HttpResponse type i.e.CustomHttpResponse and write can receive ByteBuf msg types too, it can be overridden like this:

    public void write(final ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {
        if (msg != Unpooled.EMPTY_BUFFER && !(msg instanceof ByteBuf)) {
            if (msg instanceof CustomHttpResponse) {
                onHttpResponseWrite(ctx, (CustomHttpResponse) msg, promise);
            } else {
                // if it's handling other HttpResponse types it MUST use onHttpResponseWrite again
                // or have to delegate it to super.write (that can perform redundant checks).
                // If msg is not implementing HttpResponse, it can call ctx.write(msg, promise) on it
                // ...
                super.write(ctx, msg, promise);
            }
        } else {
            // given that msg isn't a HttpResponse type we can just skip calling super.write
            ctx.write(msg, promise);
        }
    }

Important Note

It already call super.write(ctx, response, promise) before returning.

Annotations

@UnstableApi

write back to summary

write	back to summary
public void write(final ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception Overrides io.netty.channel.ChannelDuplexHandler.write. Implements io.netty.channel.ChannelOutboundHandler.write. Doc from io.netty.channel.ChannelDuplexHandler.write. Calls `ChannelHandlerContext#write(Object, ChannelPromise)` to forward to the next `ChannelOutboundHandler` in the `ChannelPipeline`. Sub-classes may override this method to change behavior. Parameters ctx:ChannelHandlerContext Doc from io.netty.channel.ChannelOutboundHandler.write. the `ChannelHandlerContext` for which the write operation is made msg:Object Doc from io.netty.channel.ChannelOutboundHandler.write. the message to write promise:ChannelPromise Doc from io.netty.channel.ChannelOutboundHandler.write. the `ChannelPromise` to notify once the operation completes Annotations @Override Exceptions Exception: Doc from io.netty.channel.ChannelOutboundHandler.write. thrown if an error occurs

public void write(final ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception

Overrides io.netty.channel.ChannelDuplexHandler.write.

Implements io.netty.channel.ChannelOutboundHandler.write.

Doc from io.netty.channel.ChannelDuplexHandler.write.

Calls ChannelHandlerContext#write(Object, ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Parameters

ctx:ChannelHandlerContext

Doc from io.netty.channel.ChannelOutboundHandler.write.

the ChannelHandlerContext for which the write operation is made

msg:Object

Doc from io.netty.channel.ChannelOutboundHandler.write.

the message to write

promise:ChannelPromise

Doc from io.netty.channel.ChannelOutboundHandler.write.

the ChannelPromise to notify once the operation completes

Annotations

@Override

Exceptions

Exception:

Doc from io.netty.channel.ChannelOutboundHandler.write.

thrown if an error occurs

public Class WebSocketServerExtensionHandler

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail